About JPA

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Tutorial
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JPA Web App Tutorial - IntelliJ Project

To open and run the JPA Web Application tutorial project in IntelliJ IDEA: Download and extract the project zip file: JPA Web Application - Maven Project (6KB). Open the project in IntelliJ IDEA: Select File > Open Project.... Select the guestbook-web directory and click OK. Define the Server
Tutorial
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Step 2: Define a JPA Entity Class

To store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New Java Class] dialog box, e.g. by right clicking the tutorial package node (in the [Projects] window) and selecting New > Java Class... Enter Point as the class name - use exactly that case sensitive
Manual
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JPA Query Expressions (JPQL / Criteria)

] MEMBER [OF] and the [NOT] LIKE operator. Logical operators: AND, OR, NOT. In addition, JPA queries
Manual
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DELETE Queries in JPA/JPQL

.Object class in queries (as an extension to JPA), so the following query can be used to delete
JPA Doc
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JPA Annotations for Fields

The way a field of a persistable class is managed by JPA can be set by the following annotations: Additional annotations (and enum) are designated for enum fields: Other additional annotations (and enum) are designated for date and calendar fields: Chapter 2 of the ObjectDB manual explains how to use all the above annotations.
Manual
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CRUD Operations with JPA

The following subsections explain how to use JPA for CRUD database operations:
Manual
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JPA Query Structure (JPQL / Criteria)

The syntax of the Java Persistence Query Language (JPQL) is very similar to the syntax of SQL. Having a SQL like syntax in JPA queries is an important advantage because SQL is a very powerful query language and many developers are already familiar with it. The main difference between SQL and JPQL
JPA Doc
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JPA Annotations for Callback Methods

The following annotations can mark methods as JPA callback methods: The Lifecycle Events section of the ObjectDB Manual explains how to use all these annotations on callback methods and with listener classes.
JPA Doc
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JPA Annotations for Relationships

Relationships are persistent fields in persistable classes that reference other entity objects. The four relationship modes are represented by the following annotations: Unlike ORM JPA implementations, ObjectDB does not enforce specifying any of the annotations above. Specifying a relationship
JPA Doc
109

JPA Metamodel API Types

The following interfaces and enum represent types in the JPA Metamodel API:  See the Metamodel Type Interface Hierarchy section for more details and examples.